Data storage systems are arrangements of hardware and software that typically include multiple storage processors coupled to arrays of non-volatile storage devices, such as magnetic disk drives, electronic flash drives, and/or optical drives, for example. The storage processors service storage requests that arrive from host machines and that specify files or other data elements to be written, read, created, or deleted, for example. The storage processors run software that manages incoming storage requests and performs various data processing tasks to organize and secure data stored on the non-volatile storage devices.
In order to protect the data they store, data storage systems have sometimes used data encryption. In some previous systems, data encryption has been provided by one or more disk controllers associated with specific disk drives of the storage system.